Lathe



Jan. 18, 1938;

F. A. FRITZSCH LATHE Filed July 17, 1955 11 Sheets-Sheet l Jan. 18, 1938.

F. A. FI'RITZSCH LATHE Filed July 17, 1935 I ll SheetsSheet 2 Jan. 18, 1938.

F. A. FRlTZSCH LATHE Filed July 17, 1935 11 Sheets-Sheet 3 Jan. 18, 1938. rF.-A. FRrrzscH 2,105,913

- LATHE Filed July 17, 1935 11 Sheets-Sheet 4 '11 Sheets-Sheet LATHE Filed July 17, 1935 F. A. FRITZSCH ww aw Mm mu Jan. 18, 1938.

m\ w mm Jan. 18, 1938. FvAHFRITZSCH Q 2,105,913

LATHE Filed July 17, 1935 ll Sheets-Sheet 6 l I I i i l j/w/ewroz' Jan. 18, 1938. F. AVFRrrzs cH LATHE Filed July 17, 1955 11 Sheets-Sheet 7 Jan. 18, 1938.

F. A. FRITZSCH LATHE Filed July 17, 1935 11 Sheets-Sheet 9 I? l/Vl/EA/OPJ Jain. 18, 1938. F. A. FRITZSCH LATHE Filed July 17, 1955 11 Shets-Sheet 1o NQMAQ Jan. 18, 1938. F. A. FRITZSCH LATHE Filed July 17, 1955 ll Sheets-Sheet ll Patented Jam-1 8. 193.8

Frank A. Fritzsch, Cincinnati, Ohio, assignor-to The Lodge & .Shipiey Machine 'liool Company,

Cincti, Ohio, a corporation of Ohio Application July 17, 1935. Serial No. 31,855

as cm. (oil. 82-21) My invention relates to a metal cutting machine employing a work support and a tool support having movement therebetween for the cutting operation, and is exemplified as of the lathe type, wherein the movements of a cutting tool or cutting tools are automatically controlled for operation selectively or in unison, and wherein the work may be selectively operated upon from relatively opposite sides bycutting tools arranged either singly or in gangs. The term'metal includes similar and substitute materials.

It is the object of my invention to provide. a machine, of this character embodying simple control and operating means for providing a cycle or cycles of movements of a cutting tool or cutting tools; further, to control the paths of relatively movable cutting tools in timed relation to one another; and, further, to provide non-interfering relations between the controls for the cutting tools at theopposite sides of the work, and for operating the various mechanisms in proper sequence and in selected directions and paths for providing a multitude of cutting cycles.

It is the object of myinvention, furthen'to provide novel electrical control means for various automatic changes in movement of the cutting tool or cutting tools; and, further, to provide novel means for exactitude of the diameters and shoulders produced on work pieces.

My invention consists in novel means for accomplishing these various objects; further, in providing novel means of placing the movements of the cutting tool or cutting tools in consonance with the rotations of the spindle rotating theworkwhile the cutting operation or operations are being performed, and of quick traversing the cutting tool or cutting tools for rapidity of return or idle movements of the tool or tools; and, further, in automatically controlling such movements by electrical devices in novel manner.

My invention consists, further, in automatically placing the cutting tool or tools in train with an independent electric motor or motors for quick traverse idle movements of the tool or tools; further, in providing a separate reversible electric motor or motors for such quick traverse movements; and, further, in providing novel means for transition between spindle drive for feed movements of the cutting tool or tools, and quick, rapid traverse drive for the idle movements of the cutting tool or cutting tools, and novel control means for the same.

My invention consists, further, in novel means controlling the relations of carriage and tool slide movements, and in novel related spindle drive and independent quick traverse drive for the carriage and tool slide; and, further, in novel control means for controlling the related actuations between a plurality of the same.

, ture or fixtures and be grasped in suitable manner so as to'rotate at a desired cutting speed.

The invention will be further r'eadily understood irom the following description and claims, and from the drawings, in which latter:

Fig. l is a side elevation of my improved device, partly broken away.

Fig. 2 is a plan view of the same.

Fig. 3 is a cross-section of a detail of carriage latching means, taken on the line 33 of Fig. 1.

Fig. 4 is a cross-section of the same, taken on the line 6-4 of Fig. l. v Fig. 5 is a head end elevation of my improved device.

'Fig. 6 is a vertical longitudinal section of a detail of the driving mechanism from the spindle to the rear tool actuating means, taken on the line 6-6'0f Fig. 5. 30

Fig. '7 is a vertical longitudinal section of a detail of driving mechanism between the spindle line il of Fig. 5. I

Fig. 8 is a. horizontal longitudinal section of a detail of driving mechanism between the spindle and the respective tool actuating means, taken on the line 8--3 of Fig. 5.

Fig. 9 is a vertical longitudinal section of a detail of the same, taken on the line 9-9 of Fig. 8.

Fig. 10 is a vertical longitudinal sectional detail of the same, taken on the line iill0, of Fig. 8.

Fig. 11 is a vertical cross-section, taken on the line H-H of Fig. 1, partly broken away, showing the related feed and quick traverse driving means for the front tool support.

Fig. 12 is a cross-section, taken in the plane of the line i2-i2 of Fig. 15, showing the dwell mechanism for the end of the feeding movement of the front tool support.

, Fig. 13 is a cross-section of the same, taken on the line 93-43 of Fig. 12.

Fig; 14 is a cross-section, taken in the plane of the line iii-4d of Fig. 15, partly broken away, 55

showing quick traverse control switches for the movement of the front tool.

front tool support.

Fig. 15 is a longitudinal section, taken in the plane of the irregular line |5-|5 of Fig. 11, partly broken away, showing the driving and control mechanism in the front control box.

Fig; 16 is a cross-section of a detail of the same. taken in the plane of the line l5-il of Fig. 15, showing the reversing control for the quick traverse motor.

Fig.1? is a cross-section of the same, taken in the plane of the line of Fig. 16.

Fig. 17a is a perspective view of the clutch between the nut and the cam sleeve.

Fig. 18 is a cross-section, taken in the plane of theirregular line |2-|2 of Fig. 15, showing a detail of the control for the dwell and reversing mechanism.

1 1g. 19 is a developed plan view of the driving cam between the respective quick traverse motors and the operating shafts'for the respective tool supports.

Fig. 20 is a developed plan view of the dwell cam for control of the final portion of feeding Fig. 21' is a plan section of the rear control box,

taken on the line 2|-2| of Fig. 5, and partly broken away.

Fig. 22 is a vertical cross-section of the rear lectlve speeds, shown accomplished by'a main electric motor 22 (Figs. 1, 2 and 5) mounted in-a compartment 29 in the base 22 of the machine control box mechanism, taken on the line 22-22 of mg. 2,. and partly broken away. 1

Fig. 23 is a longitudinal section of the same, taken in the plane of the line 22-22 of Fig. 22, and partly broken away.

Fig. 24 is a section in the planeof the line 24-24 of Fig. 22, showing the switch operating drum for the rear'transverse motor.

Fig. 25 is a cross-section of a detail or the fluid brake pump for arresting coasting of the rear tool support at the end of its reverse traverse movement, taken on the line 25-25 of Fig. 23.

Fig.-26 is an axial section of the fluid control valve for the fluid pump, taken on the line 25-45 of Fig. 21, and partly broken away.

Fig. 27 is a vertical cross-section, taken on the line 2|-21 of Fig. 2, and partly broken away, showing the front and rear carriages and tool slides and their mountings.

Fig. 28 is a vertical longitudinal section of front carriage mechanism, taken in the plane of the irregular line 22-22 of Fig. 27, and partly broken away.

Fig. 29 is a detail of the front tool slide clamp, taken on the line 22-22 of Fig. 2.

Fig. 30 is a cross-section of the same, taken on the line 25-25 of Fig. 2.

Fig. 31 is a horizontal section of the front carriage. partly broken away, taken in the plane of the line 2|.2| of Fig.

Fig. 32 is a cross-section of the rear carriage,

taken in the plane of the line 22-22 of Fig. 27,

g and partly broken away.

I slide actuating cam.

Mg. 33 is a rear view of the rear carriage,

I partly broken away.

- paths of a turning cycle; and,

Figs. 40 to 43 inclusive are diagrammatic representations showing tool positions in different paths of a facing cycle. v i

'tool actuating shaft ing driving connection with the rear tool actuating shaft 52, for feeding actuations of said shafts In the present exemplification of my invention Q a piece of work (Figs. 1 and 2) is upported between ahead center 2 and a tail center 2. The head center is in a drive spindle 4, having a face plate 5, with which the work rotates, being connected therewith by a suitable dog '5. The tail center is in a tail spindle slidable endwise in a bearing 2 in a tail stock I, for attachment release of the work, as by a handle", having I,

usual rack and pinion connection with the sleeve,

the sleeve being clamped in'the hearing by clamping means operated by a handle II.

The work is operated upon by suitable tools exemplified as a front toolor tools |4 (Figs. 1 and 2) suitably clamped to a front tool slide i5, movable toward and from'the work along guideways I of a front carriage l'l, slidable lengthwise of the bed ll of the machine on guideways i2, and by a rear toolor tools 20 suitably clamped to a rear tool slide 2| movable toward and from the work on guideways 22 of a rear carriage 22, movable lengthwise of the bed on guideways 24. The tail stock is also adjustable lengthwis'eof the bed on these guideways, and is'arranged to be clamped in adjusted positions by suitable clamping means. clamped by clamping nuts 25. The respective tool slides and the carriages form tool supports, either individually or collectively.

Thehead spindle 4 is suitably rotated at se under the head stock 2|. Areleasable louvre plate 22 closes the front end of this compartment.

A cross shaft 22 is journaled in the head stock and has a pulley 24 thereon,a belt 25 being regears may have others of difi'erent gear ratiossubstituted therefor for rotating the spindle at desired speed. A closing plate 45, releasably secured to the head stock by bolts 45, holds the change'gears on their respective shafts. A worm 41 on the cross shaft 42 meshes with a worm wheel 45 fixed to the spindle for rotating the spindle.

vceived over this pulley and a pulley 25 on the Shafts 5|," 52 extend lengthwise of the bed for moving the tool supports respectively at the front and rear of the bed. Feeding movements are imparted to these shafts for moving the respective tool supports at various speeds which have definite relations to the speed of rotation of the head stock spindle or work rotating means, accomplished by trains of gearing, including speed change gearing, and operatively connected with the work rotating means for consonance of tool feed with work rotation.

Thus the head stock spindle has a gear 52 fixed thereto, (Figs. 1, 2, 5, 6, '7 and 8), which meshes with a gear 54 fixed on a shaft 55 journaled in the head stock, and having change pinions 52,

5'! thereon for driving two trains of speed change gearings 52, 52 for respectively driving a front shaft "having driving connection with thefront 5| and a rear shaft 2| havat various speeds. A shear pinlil is between the gearing 52 and the shaft Ill, and a shear pin II is between the gearing l0 and the shaft SI for safety. A 'cover plate 02 releasably secured to the end of the frame by bolts 63 retains said speed change-gears on their respective shafts.

' Means are also provided for imparting quick traverse movements to said shafts 5i and B2, and 'for selectively imparting said feeding movements and said quick traverse movements, the latter in forward as well as reverse direction.

These means are shown located in control boxes 66, 68 respectively at the front and at the rear of the head end of the machine. The control boxes are suitably secured as by bolts 01, 68 to the respective sides of the head stock.

The front shaft 60 is journaled in bearings 89 in the front control box and in a bearing 10 in the head stock. It has a worm ll thereon, which meshes with a worm-wheel I2, rotating loosely on a cross-shaft I3 (Figs. 7 and ll.) journaled'in bearings Id, it in the front control box.

A longitudinally movable sleeve it (Figs. 11 and 15) is on this shaft and has a spiral gear ll thereon, which meshes with a spiral gear l8 on a sleeve I0, which has operative connection with a lengthwise actuating shaft 8%, coupled to the tool actuating shaft 5i, which is an extension thereof.

The rear shaft 69 is iournaled in bearings 85,-

82 in the frame of the rear control box and a bearing 83 of the head stock. (Fig. 6). It has a worm 8d thereon, which meshes with a worm-' wheel 86 (Figs. 6 and 22), rotatively loose on a cross shaft 86, journaled in bearings Bl, 8B of the rear control box. This shaft has a longitudinally movable sleeve thereon, having thereon a spiral gear 90 meshing with a spiral gear 911, on a shaft 92, extending lengthwise of the machine and journaled in bearings 93, 9% (Fig. 23) of the rear control box. Meshing gears 95, 96 are on this shaft and on the tool actuating shaft 52, which is in effect an extension of the shaft 92.

Each of the shafts I3, 86 has means mounted thereon, (Figs. 11 and 22), including the respective longitudinally movable sleeves I6, 89 for rendering the spindle drive or the quick traverse drive efiective upon the respective actuating shafts 5t, 52, these means being similar. The device for actuating the shaft Si is described and that for the shaft 52 has its parts designated by similar but primed reference numerals.

Separate reversible quick traverse electric motors I05, E02 are provided (Figs. 1, 2, 5, 15 and 23) for quick traversing the respective front and shaft The rotor of the rear quick traverse motor I02 (Figs. 22 and 23) is connected with a shaft H0 journaled in bearings Iii of the control box 66 :and having a spiral pinion H2 thereon, which meshes with a spiral gear H3 fixed, as by a pin I lit, to the shaft as.

There are connecting means (Fig. 11) between the gear 12 and the longitudinally movable sleeve it shown as a clutch H6 comprising internal teeth on the gear 72 and outer peripheral teeth on the slidable sleeve. Lengthwise sliding of the sleeve in one direction disengages the clutch, and

sliding movement of the sleeve in the'opposite direction engages the clutch. A spring I" in asocket N8 of the lengthwise movable sleeve be tween a flange I II on the shaft Iland the bottom of said socket tends normally to engage said Automatic releasing means are provided for the clutch under the influence of the quick traverse motor. The automatic releasing means are actuated by a preponderance of motion of the quick traverse motor over the motion imparted by the feeding train from the spindle. These releasing means are shown as comprising coacting cam teeth I2I, I22 (Figs. 11 and 19), respectively on proximate ends of the lengthwise movable sleeve and the hub of the gear its...

When motion is to be transmitted from the feed gearing through the clutch and longitudinally movable sleeve, (Figs. 11 and 19') the quick traverse motor is inactive, its rotor being rotated idly by means of the camteeth, andthe gears I01, I06, without lengthwise movements of the sleeve I6 to disengage the clutch.

When, however, motion is'transmitted from the quick traverse motor, positive rotation is imparted to the gear I08 and the shaft It, in either directiomwhich causes rotation of the cam teeth on the gear I00 either at greater speed than the speed of rotation of the cam teeth on the sleeve 16 imparted by the feed gearing from the spindle, or reverse to said last-named rotation, resulting in angular movement between the respective cam teeth, with the result that lengthwise movement is imparted to the sleeve I6 by a climbing between the cams, thereby disengaging the clutch H6 and rotating the sleeve I6 at the speed imparted by the quick traverse motor in either direction and unqualified by the feed gearing.

There is a slight oifset I23 in the engaging faces I24,1I25 of the cam teeth. (Figs. 11 and 19.) These engaging faces which coact when the quick traverse motor is rotating in forward traverse direction, in which direction of rotation the gears 72, I08, driven respectively by the feed gearing and the quick traverse motor, are rotating in the same direction, the gear I03, however, rotating at a greater speed than the gear it. During such rotations of the gears the engaging faces act as cams for disengaging the clutch lid, and the ends of the teeth of the cam on the gear I00 rest in the offsets 52%, forming a stop to hold the sleevein longitudinally moved position for aiding in maintaining release of the clutch lit. The longitudinal movement of the sleeve 76 is limited by engagement of its clutch end with the flange i I9 while the cam. teeth are still in engagement for rotating the sleeve, the sleeve rotating with the shaft it. I

As soon, however, as the quick traverse motor is deenergized and the gear I 00 ceases to be rotated thereby, the end wall of this offset, which is a camlike structure, is released from the tooth in engagement therewith for reverse lengthwise movement of the sleeve It and re-engagement of the clutch IIS by the action of the spring ill.

The deenergizing of the quick traverse motor in forward direction takes place at the end of tie-=- sired quick traverse forward movement of the tool. It is desired to continue movement of the tool in feeding direction at the end of such quick forward traverse. The transition from preponderance of quick traverse movement to slower feeding movement of the tool is caused by release movement between the engaging faces in which the offset I23 is located, resulting in immeamiable di ent or the clutch IIt/i'or placing-the two portions of the screw or actuating enmem shalt together in lengthwise and rotativedirecthe ieeding inilu'ence oi the feed gearingwhen the quick traverse-motor is rotated in reversedirection for reverse quick traverse. an opposite rotative relation between the coasting cam teeth (Figall andlQ) takes placeior .moving the sleeve I8 endwise and disenii l l the clutch II8. reverse rotation between the' gear Ill and the gear I! taking place. consequent reverse quick traverse movement of the tool takes place in its cycle oi'movements, at the end oi which it is desired that movement or the tool shall cease, the cycle having been completed.- For insuring such cessation oi movement 01' the tool, reengagement oi the clutch H8 is prevented, by holding means to hold the connecting meansor clutch in released or disengaged relation, as by providing the opposite engaging laces I28, I21

01 the cam teeth Ill, I22 (Figs. 11 and 19) with.

a resting face or land I 28, and driving faces I28, I88, such land being shown on'one oi the series of teeth and such driving faces being shown on both series of teeth. The land is sumciently wide to prevent retraction of the sleeve by the spring I I1, and forms a latch for the sleeve.

When the quick traverse motor is deenergized while rotating inreverse direction, the clutch.

II8 remains in unclutched relation, thereby stopping all feeding and traversing movements of the tool. i

The shaft I8 is provided with hand operating means, as by providing it with a polygonal end Ill for receiving, a suitable wrench, employed in machine setting operations.

Similar means areprovided between the gears 88, II: and the sleeve 88 (Fig. 22), similar parts being-designated by similar but primed reference numerals.

The sleeve I9 (Figs. 11 and 15) has bushings I34, I38 thereon rotatable therewith, journaled in a bore I38 in the control box 68, the bushing I34 having a radially extending annular flange I3] thereon received in a rabbet I88 surrounding said bore and shouldered in the bottom of the rabbet. The sleeve 18 has spline connection I38 with a nut I40 threaded to the lengthwise actuating shaft or screw 80. The directionsot rotations of the sleeve determine the directions of movements of the tool.

The screw 80 is coupled to its extension 8| by a coupling I for endwise rigidity between the screw and its extension, and for permitting the extension to be rotated with relation to the screw. This coupling is exemplified as comprising a cup I42, having threaded connection with a head I of the screw, being pinned to said head. A collar I48 is flxed'to the end of the extension, to form a shoulder I48, against which the inwardly extending flange I48 of the cup is clamped by a clamp nut I88 threaded over the threaded inner endIiI oi. said extension.

The extension has a threaded portion I 82, to form an auxiliary screw, rotatable in a nut I58 (Figs. 27, 28 and 31). The nut 18 fixed, as

by bolts I84. to the lower face of a cam plate I88.- The extension is rotatable on the screw "by releasing the clamp nut I88 and locating a suitable turning handle or wrenchover the polygonal outer end I8 of the, extension. The extension is rotated to position the carriage lengthwise of the bed, the carriage being clamped in adjusted position to the bed by clamps I51 (Fig. 1). After adjustment the clamp nut I50 is again clamped for rigidly holdguideways I82 in the carriage (Figs. 27, 28 and 81). The lengthwise movement of the cam plate is determined by the limits of movement or the nut III, which is movable in a recess I88 01' the carriage between shoulders I, III at the.

ends or said recess.

The tool slide is provided with an abutment which cooperates with the walls or the cam in the cam plate, shown as a roller I88 oh a stem I", fixed in a bearing I88 0!. an adjustable block I88. Thev roller is held in rotative relation to the stem and is held toward the adjustable block by the head Ill of said stem.

A screw III is journaled in a bearing in (Figs. 27- and 29) on the tool slide I8 and is held endwise therein, and is provided with a knob I'll by means or which this screw is manually rotated, suitable graduations being provided for the setting of the knob. The screw has threaded enc sement in a threaded -bearing Ill of the adjustable block I88 for adjusting the tool slide lengthwise of its guideway in the carriage.

The tool slide is clamped in adjusted position to the adjustable block by a clamp I18 (Figs. 29 and 30), movable endwise in a hole I18 in the tool slide and provided with a slot II'I, forming a iip I18, the adjustable block being provided with a ledge I18 received in said slot.

And endwise movable cam bar I80 is movable endwise in a bore I8I in the tool slide and has tated outwardly to release the clamped relation 01 this clamp.

During the time that the nut I 53 is moved lengthwise by the screw in the recess I83 between theabutments I84, I88, (Fig. 28), movement takes place of the cam plate and the slot therein lengthwise of the carriage. The coaction between the walls or said cam slot and the roller I88, with the carriage stationary on its ways, causes movement oi the tool slide toward or from the axis of. the work, depending on the direction or movement or the cam plate and the direction or inclination of the slot therein,

- and the contour of said s1ot. In practice, difi'erent cam plates having slots conIorming to the work to'be performed, are substituted for one another in the carriage, and are readily attached to the nut- I53 by removal and reclamping of the bolts I84, and by removal and replacement oi.' the top plate I81 01 the carriage. which is releasably secured to the body of'the carriage by bolts I88. 4

Endwise movement of the screw shaft after engagement of the cam plate with the respective End thrust means are provided for the nut I40, comprising a sleeve 20 I, journaled about the outer periphery of the inwardly extending hub 202.of the bearing I 32. The sleeve 20I is held endwise with relation to the bearing, (Figs. 12 and 15), as by means of an end thrust member 203, shown as a roller of frusto-conical form provided with a stem 204 rigid therewith and having journal portions 203, 206 and annular flanges 201, 20k Bearing rollers 203 are located about said journal portions. The flanges and bearing rollers ,are located in the bore 2l0 of a sleeve 2I I, the wall of the bore forming the outer bearing or runway for said bearing rollers. The upper end of the stem is threaded for receiving a nut 2I2 clamped against the flange 201, the sleeve being located between the roller 203 and said nut in such manner as to permit snug rotation of the roller, its stem and the nut.

The sleeve 2 has threaded connection in a bearing 2I3 therefor in the wall of the control box and'is rotatable therein for axial adjustment of the roller, this sleeve being held in adjusted positions by means of a set screw 2I4 threaded in the wall of said threaded bearing and bearing upon the sleeve for clamping the same in adjusted position.

The sleeve 20I is provided with a groove 2I5 (Figs. 15 and 20) in which the roller 203 is located. This groove has slanting side faces forming and thrust walls corresponding in form to the inverted frusto-conical form of the roller. The roller is endwise adjustable by means of the threaded connection 2I3, (Fig. 12) for endwise locating the sleeve 2 and taking up play and wear between the coasting faces of the cam and roller.

End thrust ball bearings 2I6, 2" are located in an inner annular rabbet 2I3 in the sleeve 20I, being located between the bottom of said rabbet and a cap 2I9 for the end of said rabbet secured to said sleeve (Fig. 15) These ball bearings comprise an intermediate raceway 220, forming an inwardly extending annular flange located in an outer annular groove of the nut I40, formed by forming a rabbet in said nut to form one wall of the groove and a nut 22I threaded over the end of said nut I40. This construction exemplifies means for reducing the friction of the end thrust of the nut I40 during either direction of axial movement of the screw respectively for forward and reverse movements of the tool.

It is desired to impart a dwell at the end of the cutting movement, it being understood that the present invention is adapted for high speed operation employing tools of high speed steel, which are somewhat brittle. It is desired that the end of the feeding movement of the tool be at reduced speed for insuring accuracy and a clean runout at the end of the out. For accomplishing this in the present exemplification longitudinal movement is imparted to the nut I40, opposite to the feeding movement of the tool so as to reduce the speed of this feed.

An intermediate sleeve 222 has spline connection 223 with the nut I40 and is interposed between the sleeves I9 and 20I about the nut (Fig. 15). The sleeve 222 and the sleeve 20I are provided with engaging clutch members to form a clutch 224, shown as internal teeth on the sleeve 222, and external teeth on the cap 2I9 wh ch is part of the sleeve 20I. These teeth are normally disengaged. Means are provided, acted on by one of the feeding parts, for engaging this clutch. When this clutch is engaged the sleeve 20I is connected with the nut I40 for rotating therewith.

The groove 2II is formed as a cam groove so that when such rotative motion is imparted to feeding movement of the screw and reducing the speed of feeding movement of the tool, so that the movement of the tool is the differential between the opposite axial movements imparted by the nut I40 and the sleeve 20I. The cam draws the nut endwise opposite to the direction of feeding travel of the screw with increasing speed, so that at the completion of the feeding movement, the nut is moved by the cam axially at substantially the axial feeding speed of the screw, to practically nullify said feeding movement, whereby the forward feed of the tool diminishes and ceases, enabling the tool to finish the cutting with reducing strains, enabling sharp comers and shoulders to be turned, avoiding the appearance of steps in the turned work, and providing a clean runout for the tool.

The means exemplified for axial movement of the intermediate sleeve 222, for engaging the clutch 224 (Figs. 11, 15 and 18) are a finger 221 in an annular groove 223 in said sleeve, the finger being fixed to a rock shaft 229 journaled in the control box 65, and having on it a pinion 230, which is meshed by a rack 23I, on a collar 232. The collar is on a reduced end 233 of an axially movable bar 234. A collar 235 is fixed to this reduced extension, a spring 236 being located between the collars and moving the collar 232 for normally holding it against a shoulder 231 on said bar. The bar is slidable endwise in a bearing 238 in the casing of the control box.

The bar is provided with a rack 24I meshed by the teeth of a segment gear 242, (Figs. 15 and 18) fixed to a shaft 243, rockable in a bearing 244 protruding from the end wall of the control box. An arm 245 is also fixed to this shaft and has on it a pin 243. An engaging shoe 241 for the pin is secured to a lug 248 on the cup I42, by means of a screw 243 threaded into said shoe and extending through a slot 250 in said lug for permitting adjustment of the shoe lengthwise of the shaft or extension BI to adjust the moment of actuation of the bar 234.

The cup I42 is provided with a cam face 25l, arranged to engage the pin when the screw 80 moves in reverse direction, the pin being received in the slot between said cam face and the cam end of the shoe 241. The cup is provided with a further cam face 252, arranged to engage the pin in forward direction for lifting the pin into said slot if it should have descended below the apex between the cam faces 25I, 252.

When the screw moves forward or to the left in Fig. 15, the pin is engaged by the cam face on .the shoe 241 for rocking the segment 242 and moving the endwise movable bar 234 endwise to the right, thereby rocking the pinion 230 and rocking the finger 221 for forward movement of the intermediate sleeve 222 and consequent engagement of the teeth of the clutch 224. If in such movement the clutch teeth should be in obstructing relation to each other, the spring 236 permits the reduced end 233 to move endwise in the rack collar 232, the spring moving the rack collar and the sleeve for engaged relation in the clutch, as soon as its clutch teeth on the sleeve .222 move opposite the'tooth spaces on the sleeve A spring pressed ball 263 (Fig. 15) in a bore in the wall of the control box is arranged to. be received in a groove 266 in the longitudinally movable bar for holding said bar in position of disengaged relation of the clutch.

The extent of rotative movement of the sleeve 20f for counteracting the feeding movement of the screw depends on the amount of such retracting movement of the screw that it is desired shall take place. At the end of such retractive movement the sleeve 20l will have rotated throughout the desired angle and any portion of the cam groove, preferably a dwell creating portion thereof, may be coactive with the roller 203 (Figs. 12, 15 and 20).

Upon cessation of such feeding movement a reverse movement or traverse takes place for rotating the sleeve 20| in opposite direction-and replacing the parts in normal position. This reversing movement is a quick traversemovement. In order to cushion the consequent quick reverse rotation of the sleeve 20l, a cushion (Figs. l2, 13, 15 and 20) is provided comprising a plunger 258, having reversely inclined contact faces 269 coacting with the reversely inclined contact faces 260 of a shoe 26l secured in a slot 262 in a wall 263 between the proximate ends of the cam groove. The plunger reciprocates in a shell 264, threaded into a threaded bore 266, in the casing of the control box. A spring 266 has one end thereof located in a bore 261 of said cushion plunger, the other end of the spring being seated in a plug 268, threaded into the outer end of the shell 264. A locating screw 269 is threaded into a threaded hole in the casing, its inner end being received in a slot 210 in said shell and in a slot 21l in said. plunger for locating the cam faces 259 in proper direction for coaction with the camfaces 260.

The retracting rotation of the cam sleeve 20f is a quick traverse movement and at the end thereof the shoe 26l strikes the plunger 268 for reducing its speed. The plunger acts as a cushion. The shoe passes under the plunger and becomes located between the plunger and the roller 203 for holding the cam sleeve 20l in normal position against any rotative urge which might be imparted thereto by the rotation of adjacent parts about the axis of the screw 80.

The shaft extension 52 (Figs. 2, 27, 32 and 33) is journaled in bearings 216 of the rear carriage 23 and has a worm 216 splined thereto by a spline connection 211. This worm meshes with a worm wheel 218 on a cam drum 219 fixed to a shaft 280 journaled in bearings 2", 292 in said carriage.

The rear carriage is moved into desired position lengthwise of the rear guideways 24, as by shifting the same manually thereon. It is clamped in desired adjusted position by clamps 283, for locating the path of the crosswise movement of the rear tool slide 2!.

The cam drum 219 is provided with a cam slot 285, into which a roller 286 journaled about a stem 281, secured in a bearing 288 of an adjustable block 289, is received. This roller is held toward the adjustable block by the head 290 of said stem.

The adjustable block is adjustable in the tool slide by means of a threaded rod 29l, (Figs. 2,

-27 and 32), which has threaded connection in a threaded bore 292 of said adjusting block, and is rotatable and held endwise in a bearing 293 in the tool slide, and has thereon a knurled head 294 for rotating the same, there being a suitable index. for the knurled head.

This adjustable block has a dovetail groove 296 extending lengthwise in its upper face in which the head 296 of a clamp bolt 291 is received. The clamp bolt extends through a hole 298 in the tool slide and has'a clamp nut 299 threaded thereover for clamping the tool slide to the intermediate block after adjustment.

In the present exempliflcation feeding and quick traverse movements'of the rear tool toward and from the axis of the work only are indicated for performing such operations as facing, grooving, cutting off and the like, either complemental to or independent of the movements of the tool or tools on the front tool support, although it is obvious that movements lengthwise of the bed may also be imparted to the rear tool either in conjunction with-or independent of the crossmovements thereof, and that the mechanism for feeding and quick traverse of the front tool support and of the rear tool supportmay be selectively duplicated at the front and at the rear of the machine within the scope of my invention set forth in the accompanying claims.

In the present exempliflcation the lead of the cam drum 219 is such as to cause performance of the cutting operations of the rear tool or tools during performance of the cutting operation of the front tool or tools. Quick traverse movements may be imparted to the rear tool or tools either in forward direction or reverse direction, with intermediate feeding movements, as by imparting rapid rotations to the rear lengthwise shaft and its extension in forward or reverse directions by means of the rear quick traverse electric motor I02, or feeding rotations may be imparted to said lengthwise shaft and extension by means of the speed change train of gearing 69, which have rotations imparted thereto in consonance with the rotations of the head spindle or driving shaft for the work.

A dwell is provided for the end of extreme inward movement and extreme outward movement of the tool'slide, as by reducing the lead of the cam in the cam drum at each end thereof, (Fig. 34), as by the dwell portions 30L 302 thereof, which terminate substantially perpendicular to the axis of the drum. This provides for clean runout of the tool and the cutting of accurate corners and shoulders and prevents steps from being perceptible in turning operations at the end of the feeding movement of the tool, and for smooth and easy transitions from one direction of movement or control to another in the operation of the rear tool support.

Braking means are also provided for the rear tool support to avoid overrunning of the tool, effective at the end of tool movement in any selective direction.

In the present exemplification this braking means is exemplified as comprising a fluid pump I sage 3l l, the respective ends of which have fluid conduits 3l2, 313 connected therewith, the other of the ends of these fluid conduits having connections with passages 3 l4, 3 i 6 in the body of the control box. There is a check valve 3| 6 between said passages, shown as a ball, spring-pressed 75 1 stance, after cessation of cutting movements of ated arm 346 thereon.

by a spring 3I1 to normally seat on its seat between said passages. A threaded plug 3I6 closes the end of the bore in which said spring is located. A cross-passage 3I9 communicates with the passage 3I5, the outer end of this passage being closed by a. threaded plug 323. I

A sleeve 32I (Fig. 26) has a bore 322 provided .with an enlargement 323, forming a shoulder 324.

The sleeve is secured in a bore 325 in the body of the control box. Said bore has an annular shoulder 326 at one end of said sleeve. The enlarged bore of said sleeve is provided with a threaded outer end in which a headed plug 321 is threaded for clamping the sleeve in longitudinal direction in its bore so as to prevent leakage of fluid past said sleeve.

The outer periphery of said sleeve is provided with annular grooves 33I, 332, from which holes 333, 333 radiate into the inner bore 323 of said sleeve.

A piston 335 is reciprocable in the bore in the sleeve and is provided with a head 336 at one of its ends, arranged to contact the shoulder 33 itoward which such piston is resiliently pressed by a spring 331 between said piston and the plug 321. This piston is provided with anannular groove 338 with which theradiating holes 333,

334 normally communicate when the piston is in normal position. a

The piston is arranged to be moved lengthwise for closing the radiating holes 333 and stopping the rear tool or tools, for removal of the work and the placing of a new piece of work in the' machine.

The actuation of the piston 335 is obtained by means of an actuating arm 34I (Figs. 21, 22, 24 and 26) fixed to a shaft 342, journaled in a bearing 343, 344 of the control box. This arm car- "ries an adjusting bolt 345 arranged to beqadjusted in the arm for adjusting the moment of actuation of the piston. The shaft has an oper- The shaft 92 (Figs. 21, 22, 23 and 24) has a worm 341 thereon, which meshes with a worm wheel 348 ,fixed to a shaft 349, journaled in bearings350, 35I in .the control box 66. This shaft has,

fixed thereto a tappet wheel 352, which has thereon a tappet 353, shown as a block adjustable along a peripheral rib 354 on said wheel and fixed to said wheel in adjusted position by means of a set bolt 355. This tappet is arranged to strike the arm 346 at the appropriate mbment for actuationof the arm 34'I, in order to move the.

piston 335 into obstructing position, for braking the actuated parts of the rear mechanism at the end of reverse traverse movement thereof. The arm 346 is arranged to ride on the outer periphery of this tappet until completion of the braking I movement.

The weight and friction of the carriage on the bed is greater than the weight and friction of the tool slide on the carriage, so that cross movement of the tool slide on the. carriage is more ready than sliding movement of the carriage lengthwise of the bed during lengthwise movemen of the cam plate I55 in the carriage. This difference maybe increased by drawing up on the clamp bolts 356 acting on the guideway plate 351 of the carriage for insuring preponderance of cross slide movement. If desired, means may be,

provided for latching the cam plate I55 selec tively to the carriage and latching the carriage selectively to the bed. i

. These means are exemplified as an upright rock,

shaft 358 (Figs. 1, 3, 4, 27, and 31) Journaled ina bearing 359 in the carriage. This rock shaft at its upper'end has alatch 368 at one side of itsaxis and a clearance space 36I at the other side of its axis; At its lower end the rock shaft has a clearance space 362 at said one side of its axis and a latch 363 and a'cam contact face 364 one above the otheniatsaid other side of its axis. The upper end of the rock shaft is-also provided with an arm 365 rigid therewith, whichhas a toe 368 at said one side of its axis and a heel 361 at said other side of its axis, at the side of which latter there is a contact face 368.

A contact plate 369 and a keeper plate 318 p are secured in desired relation to each other on the lower face of the cam plate I55. respectively by bolts 311, 312, the heads of which are countersunk in-said respective plates 369, 310, the bolts being respectively threaded in threaded holes 313, 314 in the cam-plate in desired relation to the cam slot in said cam plate I55 and for desired coaction respectively with said toe 366 and the latch 366. The contact plate 369 is thicker than the keeper plate 318 so as to reach the arm 365; the keeper plate 313, the clearance space 36I and latch 363 being above the level of said arm.

A plunger 315 reciprocates in a bore 316 of the carriage and engages the heel 361.. It is spring pressed towards the heel by a spring 311 in a bore in the outer end of the plunger, resisted by a plug 318 threaded in the outer end of the bore 318. The spring and plunger normally urge the rock shaft 358 in clockwise direction looking at the top of the rock shaft, the contact face 368 limiting rotation of the rock shaft.

A cam slide 38I has acam plate 382 releasably secured thereto by screws 363. (Figs. 1, 4, and 27). This cam plate hasa cam face 384 thereon. This slide is adjustable lengthwise of the bed along a guideway 385, along which an undercut slot 386 is formed in the bed. The heads of bolts 381 are located in this slot, the bolts extending through the cam slide, nuts 388 clamping the slide in adjusted position to the bed.

A keeper plate 389 has a keeper face 390 thereon. This keeper plate is adjustable lengthwise on the cam slide and is securedin adjusted posi-- tions thereon by clamp bolts 39I passing through slots 392 in the keeper plate and threaded into the cam slide. The cam'slide and keeper plate are adjustable lengthwise of the bed and are'arranged to be clamped in adjusted positions related to the desired coaction with the latch and .cam contacting face on the lower end of the rock shaft according to desired coactions between the parts at the upper end of the rock shaft and the parts on the cam plate I 55.

The latch 360 coacts with a keeper face 393 on I with its ,nut I53 engaging the stop I for obtaining combined movements of the carriage and tool slide lengthwise of the bed in certain operations. is 'disengaged by coaction between the cam contacting face 364 and the cm 384.

the keeper plate 318 for latching the cam plate (Figs. 1, 3, 4, 2'7, and 31). This latch I The 393 is released by contact of the nose m on the contact plate as with the toe uson thearm 395, in order to permit lengthwise movement of the carriage in feedingdirection.

e=. the slide m and the plate th 811mm 1 belf'ih" obstructing relation with the faces at the lower end of the rock shaft during movement of the-carriage toward the tail stock with the slide -38I between ,said upright shaft and the tail stock,

said faces on the lower end of the upright rock shaft will ride upon-the obstructing faces on the cam slide 39I and the keeper plate thereon, re-' .s'iliently rocking. said upright shaft against the resistance [of the spring-pressed plunger 315,.

which immediately returns therock' to normal rocked positionas soonas it has passed the obstructing faces on said cam slide.

The cam slide "I and the keeperplate 399 may be adjusted lengthwise-of the bed for desired coactions with the latch and cam contacting face at the lower end of the rock shaft, or lack of such coactions, as may be respectively desired for various operations upon the work, in some of which the keeper plate 319 on the cam slide I55 is inactive.

' when forward traverse movement ofthe tool slide toward the work is to take place, the roller I56 is initially in the outer end of the cam slot edge and head end thereof across the longi- The nut IN inthe cam plate I55. (See Figs. 3, 31, and 36 to 39 inclusive.) This cam slot slants from the inner edge of said cani plate toward the outer a direction away from the axis of the centersof the lathe. In such cases the cam plate I55 is reversed on its longitudinal axis so that its cam slot I9I 'slants from its outeredge inwardly toward the head end of the lathe, as exemplified in Figs. 40 to 43 inclusive.

when such relation of the cam plate is desired,

"the bolts I54 which pass-through holes 395 in the cam plate I55 andholdit to the nut I53 (Fig.

28) are unscrewed, and the bolts 3', 312 (FigsJ '3 and 31 respectively threaded in the holes 313, 314 in the cam plate I55 for clamping the contact plate 359 and the keeper plate 319 to the.-

\ under face of the cam plate I55, are unscrewed,

Cir

and such nut and plates are fastened to the opposite face of said cam plate and at the opposite side of the longitudinal median line thereof, the bolts I54 passing through holes 395', the bolts 3' being screwed into threaded holes 313', and the bolts '3" being screwed into threaded holes 314'.

.Such various contacts and changes in relation of the latches, keepers and came take place sub-' stantially at the initiations of changes in speeds and directions of tool movement. such changes in speeds and directions of movement lengthwise of the bed and selectively toward or from the work being determined by the electric control means to-be now described.

Electrical control is provided for controlling the feeding movements. and the quick traversing movements in forward and reverse directions of v the operating shafts extending lengthwise of thebed and connecting with the tool supports, and

the moments of initiations of said movements.

Referring now to the front shaft, there is a double pole switch 49I (Figs. 15, 16, 17 and 35),-

.comprisinga control switch 492 in the reversing circuit of the front quick traverse motor III and a control switch 493 in the main motor control circuit. These switches are reversely actuated for closing the reversing controlswitch for the .quick traverse motor I 9I and opening the control switchin the main motor circuit at the'end of the feeding movement of the cutting tool and actuated-by an element concerned'in such feedingmovement, which is exemplified as the cam sleeve 29I.

A shoe 494 is located in an annular groove 495 in saidcam sleeve and moves "the shoe with the axial movement. of the cam sleeve. This shoe is ,on anarm 4Ii5,v fixed to a rock shaft 491, Jourfor operating the double poleswitch I (Fig. 17)

. comprising the control switches 492, 493 (Fig. 35) Just mentioned. a

Before such actuation 'and while the operating arm is in position shown in Fig; 17, the switch 493 for the main motor-circuit is closed and the switch 492 for the reversing circuit of the front traversing mlotor is-open, the plunger being held in this relation by means of a latch .5, shown in the form 'of -a bell-crank lever, and arranged to engage 'the head 4 I3 of the plunger for holding said control switches in the relations last stated 5 until actuation of the cam sleeve 29I for moving said sleeve endwise at the final portion .of the I feeding movement of, the tool.

When this endwise movement takes place the arm 499 is moved for releasing the latch 5, this operating arm being provided with a contact rod 4 shown in the form of a threaded rod adjusted lengthwise in a threaded bearing 4I.'I of said arm and held in adjusted position by a jam nut 413.

This contact'rod-is arranged to engage the lever latch 5, which is normally springepressed into engaging relation with the head ,4I3 by a spring 4I9.-

M2, which releases-the {button 4, normally' spring-pressed outwardly by a spring 429 for opening the control switch 493 in the main motor circuit and closing the switch 492 in the reversing circuit of the quick traverse motor I9I and placing the screw 89 under the operative influence of the quick traverse motor IIII operating in reverse,

tuation at the end" of feeding movement of the tool, returns the arm 499 to normal position for moving the plunger 2 in reverse direction and againengaging the latch 5, it being understood that these control switches control relay switches, to be hereinafter described.

A switch operating arm 42I (Figs; 14', .15 and 35) is fixedto a rock shaft 422, journaled-in a bearing 423, extending from the supporting frame of the front quick traverse motor, and having thereon a cam head 424 for'engaging rollers 425, 429 respectively on ,an operating arm 42'! of 'a double acting single pole snap control switch 429 arranged, when open, to open the forward circuit of the front quick traverse motor I9I.

It is assumed that all control and relay circuits are normally open circuits, and thisdescription refers'to the switches being open or closed accordingly, althoughit is obvious that thecircuits 75v The tripping of this lever releases the plunger groupie may be normally closedcircuits,-in which 'opcmand closed conditions of the control and relay switches would be reversed, and that other changes in electric devices and circuits may be made, without departing from the spirit of my invention'set forth in the accompanying claims.

The arm 42! is received in the longitudinal slot I91 extending lengthwise of the screw 30. There is a bore 43! in the end of this screw rod with which the slot i0! communicates. A tappet 432- is adjustable lengthwise in this bore' and meets I with the arin 42! to operate the control switch 426. A screw rod 433 has threaded connection with this tappet for adjusting the tappet lengthwise of the bore and slot for adjustable coactlon with the tappet arm 42!. The screw rod 433 has bearing in a plug 43 threaded into the outer end of this bore. The screw rod further has a collar 436 fixed to it at one side of said plug and an operating head 436 fixed to it at the other side of this plug for holding the rod to prevent its axial movement. A

' protecting hood 43! having an extension 438, is

.received over the switches and theouter end of the screw, and is suitably secured to the supporting plate !03 and has a closing cap 439 atits outer end. The extension is removable from the hood proper by having releasable connection shown as a bayonet connection 440 with the hood.

When the screw 80 is moved outwardly the 1 tappet 432 engages the tappet arm 42! and operate-s the control switch 428 in one direction at the end of the forward transverse movement at a moment determined by the adjustment of the tappet 432, and thereby places said feed shaft under rotative influence 'of'the feed mechanism in consonance with the rotative movement of the spindle. Upon retractive movement'of the screw 80, to the right as shown in'Fig. 15, the tappet 432 engages the tappet arm 42! in opposite direc- .tion for resetting the control switch 420.

The screw 60 is provided witha collar 44! (Figs. 14 and 15) threaded to the screw and arrangedto be positioned lengthwise of the screw and to be clamped in adjusted position by a clamping screw 442, drawing together a split portion of said collar for clamping the screw threads.

This collar is arranged to engage a bufier sleeve 443 movable endwise in a bearing 444 about the screw and backed by a buffer spring 445 between sad buffer sleeve and an annular shoulder 446 at the end of said bearing, outward movement of the buffer sleeve being limited by shoulders 4'! between it and said bearing. This buffer cushions the inward quick reverse traversin movement of the screw at the end of said movement.

The collar 44! is also arranged to contact the tappet arm 42! if this tappet arm should not have been moved sufiiciently by the tappet 432 upon the retraction of the latter forinsuring resetting of the switch 428.

The .collar 44! is further arranged to contact the-button 448 of a single pole control switch 449 for controlling the stopping of the reverse -traverse of the tool. This switch is physically mounted on the bearing 444.

In the present exemplification the rear tool I slide 2! is moved toward the center of the work,

first with a quick forward traverse by the forward rotation of the quick traverse motor I02, initiated by the push button 45!, (Fig. 35), which closes the switch 452 in the forward circuit of the main motor and a switch 453 in the This quick forward traverse of the slide '2! continues until the tool is nearly in actuatingrelation with the work, whereupon the forward quick traverse circuit of the quick traverse motor I02 is opened by opening a switch 434 in said circuit, (Figs. 21, 22, 23, 24 and 35), which 18.

exemplified as a single pole snap switch and having an operating shaft 466 Journaled in a bearing 466 and provided with an operating arm 4!! arranged to be engaged by a tappet 460 adjustably secured to the tappet wheel 362 for opening this switch and maintaining it open until again. actuated by said tappet moving in reverse direction for moving said. arm. and again resetting. said switch 454 after reverse actuation of said traverse motor. v v I After cessation of forward traverse movement of the tool, the tool is feddnto the work by the feed gearing including the train of change gear-'- ing 60 and by coactlon of the roller 286 with the r I -f I forward" traverse circuits of the front I-quick. traverse motor I 0! andof the 'rearcuick travs .erse motor I02. 1

cam slot 286 in the. cam drum 219 (Figs. 27 and 34). The final portion of this feeding movement is during coactlon of said rollerwith the end portion 30! having reducing lead in said 'slot, for proper finish of the cut and proper runout of the tool, forming sharp corners and shoulders I and preventing ridges in the work. At the end of .the feeding movement, aquic reverse movement of the tool takes place controlled by the actuation of a double pole reverse traverse switch,including a switch 46! for momentarily closing the reverse circuit of the quick traverse motor I02, and a switch 462 in the main Thisthe switch 40! energizes the reverse circuit of the quick traverse motor !02, whereupon the tappet wheel reverses and the tappet 466 moves in opposite direction for actuating the arm 465m reverse direction, and thereby resets the switch 46!, it being understood that the momentary closing of this switch has energized a. relay switch for maintaining the reverse circuit of the quick traverse motor I02 closed.

This reverse rotation of the tappet wheel continues until thetappet 353 moves the am 346 for rocking the shaft 342 (Figs. 21, 22, 23 and 24). This rock shaft has on it' an arm 41!, which contacts a push button 412 of a normally closed single pole switch 473 for opening this switch at the end of the reverse quick traverse of the tool. This switch is in the reversing circuit oi.- the quick traverse motor I02. This positions the tool at the end of its cycle of movements, ready to begin another cycle of its movements after.

the work 'just out has been removed and a new piece of work inserted in the machine.

In explaining the operation of the machine it will be assumed that the front toolshave movements imparted thereto to complete a cycle of operation such, for .instance, as depicted in Figs. 36 to 39 inclusive, andreference is also had to the electrical diagram shown in Fig. 35. The various 

